The present invention relates to a method and apparatus for use in making a core which is used in the casting of an airfoil having an internal cavity.
Ceramic cores for use in making airfoils have previously been made by shaping a ceramic mixture to form a green core having a configuration which is a function of the configuration of a cavity in a metal airfoil. The green core may be initially heated to improve its strength and retain surface condition. After the initial heating and burn off of organic materials, the core may be supported on a setter block and sintered in a kiln. The kiln fire process may take up to 24 hours. After the kiln fire process, voids may be left behind within the core. The voids may be filled by dipping the core in a ceramic material. The core is sintered in a kiln a second time after being dipped in the ceramic material.
Known methods and apparatus for use in making known cores are disclosed in U.S. Pat. Nos. 3,701,379; 5,014,763; 5,296,308; 6,347,660; 6,403,020; and 7,780,905. In addition, apparatus for use in making cores is disclosed in U.S. Patent Publication Nos. 2004/0159985 A1 and 2010/0319870 A1.